α-Amylase (1,4-α-D-glucan glucanohydrolase [EC3.2.1.1]) is an endo-type enzyme which randomly cleaves α-1,4 glucoside linkages of starch, glycogen etc. This enzyme is widely used industrially in starch processing, food processing, fiber processing, fermentation, pharmaceutical preparations, clinical examination and detergents, and is derived from a wide variety of sources such as microorganisms, plants and animals.
Conventionally, this industrially very important enzyme is not always satisfactory in respect of its activity and cost, and as a means for solving this problem, an increase in productivity of the enzyme and reinforcement of the catalytic ability of the enzyme have been attempted by genetic recombination and protein engineering technology, and a method of improving the reaction rate of the enzyme in an enzyme reaction system, that is, a method of activating the enzyme reaction, has been examined.
With respect to the method of activating the enzyme, there are reports on activation by adding a specific polymer to an enzyme reaction system (JP-A(W) 5-507615), activation by adding chlorine ions to specific amylase (Clin. Biochem., 16, 224-228 (1983)), the enhancement of the enzyme activity by utilizing a reverse phase micelle system obtained by adding Tween 20 (polyoxyethylene sorbitan monolaurate) to n-hexane (Biotechnol. Bioeng., 29, 901-902 (1987)), and the enhancement of the enzyme activity by adding an alkyl sulfate and/or alkyl sulfonate having an alkyl group of specific length to an enzyme reaction system (JP-A 8-256768). Further, a method of activating the enzyme in a step prior to the enzyme reaction by previously dissolving the enzyme in electrolytic water (JP-A 2000-245453) and a method of activating the enzyme by dissolving the enzyme in an exothermic inorganic salt (JP-A 2000-37186) have been reported.
With respect to the method of producing a detergent composition containing the enzyme, many literatures have reported separate after-blending of the enzyme, a bleaching agent etc. into a detergent base obtained by various granulation procedures.